Glaucoma implant device

ABSTRACT

A surgical method is provided for diverting aqueous humor from the anterior chamber of the eye. A surgical tool is provided having a hollow support member that supports a portion of an aqueous humor drainage device. The device has an elongate duct structure and preferably at least one fixation member that extends therefrom. The distal end of the hollow support member is inserted into the anterior chamber of the eye through an opening passing through the sclera. The aqueous humor drainage device is deployed from the hollow support member for placement into the eye. In one embodiment, the fixation member is realized by a tab that is spaced apart from the two ends of the elongate duct structure. In another embodiment, the fixation member is realized by a pair of tines that extend in traverse directions relative to the central axis of the elongate duct structure.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from U.S. Application Ser. No.60/741,514, filed on Dec. 1, 2005, and is a continuation-in-part of U.S.patent application Ser. No. 11/004,539, filed on Dec. 3, 2004 now U.S.Pat. No. 7,431,709, both of which are hereby incorporated herein byreference in their entireties.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates broadly to medical devices and materials forreducing intraocular pressure. More particularly, this invention relatesto medical devices and materials for diverting aqueous humor out of theanterior chamber through a surgically implanted duct passageway.

2. State of the Art

Glaucoma is a disorder of the optic nerve that usually occurs in thesetting of an elevated intraocular pressure (typically referred to as“IOP”). The pressure within the eye increases causing changes in theappearance (“cupping”) and function (“blind spots” in the visual field)of the optic nerve. High pressure develops in an eye because of impairedoutflow of aqueous. In open-angle glaucoma, the impaired outflow iscaused by abnormalities of the drainage system of the anterior chamber.In closed-angle glaucoma, the impaired outflow is caused by impairedaccess of aqueous to the drainage system. If the pressure within the eyeremains sufficiently high for a long enough period of time, total visionloss occurs. Thus, glaucoma is the number one cause of preventableblindness.

As shown in FIG. 1, the eye 10 is a hollow structure that contains aclear fluid called “aqueous humor.” Aqueous humor is formed by theciliary body 12 adjacent the posterior chamber 9 of the eye. The fluid,which is made at a fairly constant rate, then passes around the lens 14,through the pupillary opening in the iris 18 and into the anteriorchamber 20. Once in the anterior chamber 20, the fluid drains out of theeye 10 through two different routes. In the “uveoscleral” route, thefluid percolates between muscle fibers of the ciliary body 12. Thisroute accounts for approximately ten percent of the aqueous outflow inhumans. The primary pathway for aqueous outflow in humans is through the“canalicular” route that involves the trabecular meshwork (not shown)and Schlemm's canal 24.

The trabecular meshwork and Schlemm's canal 24 are located at thejunction between the iris 18 and the sclera 26. This junction istypically referred to as the “angle” 28. The trabecular meshwork is awedge-shaped structure that runs around the circumference of the eye. Itis composed of collagen beams arranged in a three-dimensional sieve-likestructure. The beams are lined with a monolayer of cells calledtrabecular cells. The spaces between the collagen beams are filled withan extracellular substance that is produced by the trabecular cells.These cells also produce enzymes that degrade the extracellularmaterial. Schlemm's canal 24 is disposed adjacent to the trabecularmeshwork. The outer wall of the trabecular meshwork coincides with theinner wall of Schlemm's canal 24. Schlemm's canal 24 is a tube-likestructure that runs around the circumference of the cornea. In humanadults, Schlemm's Canal is believed to be divided by septa into a seriesof autonomous, dead-end canals. The aqueous fluid travels through thespaces between the trabecular beams of the trabecular meshwork, acrossthe inner wall of Schlemm's canal 24 into the canal, through a series ofcollecting channels that drain from Schlemm's canal 24 and into theepiscleral venous system (not shown).

The tough outer membrane known as the sclera 26 covers all of the eye 10except that portion covered by the cornea 34, which is the thin,transparent membrane which covers the pupillary opening and the iris 18.The cornea 34 merges into the sclera 26 at a juncture referred to as thelimbus 32. A portion of the sclera 26 is covered by a thin tissue calledTenon's membrane 36, which envelopes the bulb of the eye from the opticnerve (not shown) to the ciliary region, and separates the eye from theorbital fat and forms a socket in which the eye moves. Near its front,Tenon's membrane 36 blends into the conjunctiva 30 where it is attachedto the ciliary region of the eye as shown.

In a normal patient, aqueous production is equal to aqueous outflow andintraocular pressure remains fairly constant (typically in the 15 to 21mmHg range). In glaucoma, there is abnormal resistance to aqueousoutflow, which manifests itself as increased IOP. Tonometry is themeasurement of IOP. In primary open angle glaucoma, which is the mostcommon form of glaucoma, the abnormal resistance is believed to be alongthe outer aspect of trabecular meshwork and the inner wall of Schlemm'scanal 24. Primary open angle glaucoma accounts for approximatelyeighty-five percent of all glaucoma. Other forms of glaucoma (such asangle closure glaucoma and secondary glaucomas) also involve decreasedoutflow through the canalicular pathway but the increased resistance isfrom other causes such as mechanical blockage, inflammatory debris,cellular blockage, etc.

With the increased resistance, the aqueous fluid builds up because itcannot exit fast enough. As the fluid builds up, the IOP within the eyeincreases. The increased IOP compresses the axons in the optic nerve andalso may compromise the vascular supply to the optic nerve. The opticnerve carries vision from the eye to the brain. Some eyes seem moresusceptible to IOP than other eyes. While research is investigating waysto protect the nerve from an elevated pressure, the therapeutic approachcurrently available in glaucoma is to reduce the intraocular pressure.

The clinical treatment of glaucoma is typically carried out in astep-wise manner. Medication often is the first treatment option.Administered either topically or orally, these medications work toeither reduce aqueous production or they act to increase outflow.Currently available medications have many serious side effectsincluding: congestive heart failure, respiratory distress, hypertension,depression, renal stones, aplastic anemia, sexual dysfunction and death.Compliance with medication is a major problem, with estimates that overhalf of glaucoma patients do not follow their correct dosing schedules.

When medication fails to adequately reduce the pressure, lasertrabeculoplasty often is performed. In laser trabeculoplasty, thermalenergy from a laser is applied to a number of noncontiguous spots in thetrabecular meshwork. It is believed that the laser energy stimulates themetabolism of the trabecular cells in some way, and changes the cellularmaterial in the trabecular meshwork. In a large percent of patients,aqueous outflow is enhanced and IOP decreases. However, the effect oftenis not long lasting and a significant percentage of patients develop anelevated pressure within the years that follow the treatment. The lasertrabeculoplasty treatment is typically not repeatable. In addition,laser trabeculoplasty is not an effective treatment for primary openangle glaucoma in patients less than fifty years of age, nor is iteffective for angle closure glaucoma and many secondary glaucomas.

If laser trabeculoplasty does not reduce the pressure sufficiently, thenincisional surgery (typically referred to as filtering surgery) isperformed. With incisional surgery, a hole is made in the sclera 26adjacent the angle region. This hole allows the aqueous fluid to leavethe eye through an alternate route.

The most commonly performed incisional procedure is a trabeculectomy. Ina trabeculectomy, a posterior incision is made in the conjunctiva 30.The conjunctiva 30 is rolled forward, exposing the sclera 26 at thelimbus 32. A partial scleral flap is made and dissected into the cornea.The anterior chamber 20 is entered beneath the scleral flap, and asection of deep sclera 26 and trabecular meshwork is excised. Thescleral flap is loosely sewn back into place. The conjunctiva incisionis tightly closed. Post-operatively, the aqueous fluid passes throughthe hole, beneath the scleral flap and collects in a bleb formed beneaththe conjunctiva 30. The fluid then is either absorbed through bloodvessels in the conjunctiva 30 or traverses across the conjunctiva 30into the tear film. Trabeculectomy surgery of this nature is extremelydifficult and only a small fraction of ophthalmologists perform thisprocedure. In addition, it is very time consuming and physicians are notreimbursed for the time it takes to perform the surgery and it istherefore rarely performed.

When trabeculectomy doesn't successfully lower the eye pressure, thenext step, and usually the last, is a surgical procedure that implants adevice that shunts aqueous humor to control the IOP. One such implantdevice, as shown in U.S. Pat. No. 6,050,970 to Baerveldt, is a drainagetube that is attached at one end to a plastic plate. The drainage tubeis a flow tube between 1.0 and 3.0 French (and preferably with an innerdiameter of 0.3 mm and an outer diameter of 0.6 mm). An incision is madein the conjunctiva 30, exposing the sclera 26. The plastic plate is sewnto the surface of the eye posteriorly, usually over the equator. A fullthickness hole is made into the eye at the limbus 32, usually with aneedle. The tube is inserted into the eye through this hole. Theexternal portion of the tube is covered with either sclera or othertissue. The conjunctiva 30 is replaced and the incision is closedtightly. With this shunt device, aqueous drains out of the eye throughthe silicone tube to the bleb, which is a thin layer of connectivetissue that encapsulates the plate and tube and then to the surface ofthe eye. Aqueous drains out of the bleb and to the surface of the eye.Deeper orbital tissues then absorb the fluid. The plate typically has alarge surface area in order to wick and disperse fluid, whichfacilitates absorption of fluid in the surrounding tissue. These disksare generally made of silicone rubber, which serves to inhibit tissueadhesion as the plate becomes encapsulated by the connective tissue ofthe bleb. The disks can be as large as 10 mm in diameter and areirritating to some patients.

Other implant devices are shown in U.S. Pat. No. 6,468,283 to Richter etal. and U.S. Pat. No. 6,626,858 to Lynch et al., respectively. TheRichter implant device is a tubular structure that shunts aqueous humorfrom the anterior chamber to a space between the conjunctiva 30 and thesclera 26. The Lynch implant device is a tubular structure that shuntsaqueous humor from the anterior chamber through the trabecular meshworkand into Schlemm's canal 24. These implant devices are described asbeing formed from silicone, Teflon, polypropylene, stainless steel, etc.These implant devices also typically require precise placement away fromthe angle and the iris in order to prevent interference with the irisand/or to avoid occlusion of the drainage lumen by ocular tissue (forexample, the fibrous tissue of the iris and/or the sclera that may plugthe drainage lumen). In addition, such implant devices typically includea unidirectional valve to minimize hypotony (low IOP) in the anteriorchamber of the eye. However, the desired flow control provided by suchvalves is difficult to maintain and are prone to failure. Lastly, theseshunt devices are relatively stiff and have been shown to erode throughthe ocular tissue wall adjacent thereto over time.

Thus, there remains a need in the art to provide an implant device forthe treatment of glaucoma that is realized from a biocompatible materialwhich will not encapsulate in the eye and that enables control over IOPwithout the need for large surface area plates and possibly without theneed for unidirectional flow control valves.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide an implant devicefor the treatment of glaucoma that is realized from a biocompatiblematerial that will not encapsulate in the eye, thereby avoidingocclusion of the implant device by ocular tissue and enabling controlover IOP without the need for a large diameter plate.

It is a further object of the invention to provide an implant device forthe treatment of glaucoma that utilizes a small size duct structure,thereby enabling more flexible and less precise positioning of the ductstructure within the ocular cavity and also enabling multiple devices tobe implanted, if necessary.

In accord with these objects, which will be discussed in detail below, asurgical implant device for treating glaucoma includes an elongate ductstructure that provides a fluid passageway for diverting aqueous humorfrom the anterior chamber of the eye and at least one fixation memberthat extends radially outward from the elongate duct structure. In oneembodiment, the at least one fixation member is realized by a tab thatis spaced apart from the two ends of the elongate duct structure. Inother embodiment, the at least one fixation member is realized by a pairof tines that extend in traverse directions relative to the central axisof the elongate duct structure. The tines are spaced apart along thelength of the elongate duct structure for positioning on opposite sidesof the sclera in the vicinity of the angle of the eye during use. Theelongate duct structure and the at least one fixation member arepreferably formed from an elastomeric material. In the preferredembodiment, such elastomeric material includes polyisobutylene and aglassy segment. Such material is advantageous in that it will notencapsulate within the ocular environment and thus provides anunobstructed flowpath that diverts aqueous humor from the anteriorchamber. Such material also allows for smaller, simpler designs withoutthe need for a large diameter plate commonly used in the prior artdesigns, and thus promotes quicker healing.

According to the preferred embodiment of the invention, the elongateduct structure is realized from a soft polymeric material with ahardness less than Shore 80A and defines a lumen channel having adiameter in a range from 0.0025 inches to 0.006 inches.

In another aspect of the invention, a surgical tool is provided forinserting a distal portion of the aqueous humor drainage device into theanterior chamber of the eye. Moreover, the surgical implant device andsurgical tool are preferably used as part of a surgical method to divertaqueous humor to a pocket region formed between the conjuctiva-scleraand Tenon's membrane.

Additional objects and advantages of the invention will become apparentto those skilled in the art upon reference to the detailed descriptiontaken in conjunction with the provided figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a prior art illustration showing anatomic details of the humaneye.

FIG. 2A is a side view of an aqueous drainage device in accordance withthe present invention.

FIG. 2B is a front view of an aqueous drainage device in accordance withthe present invention.

FIGS. 3A through 3D are schematic illustrations of an inserter devicefor deploying the aqueous drainage device of FIGS. 2A and 2B inaccordance with the present invention; FIG. 3A is a schematiccross-section of the entire inserter device; FIGS. 3B and 3C areschematic cross-sections of the front portion of the inserter device;and FIG. 3D is a schematic cross-section of the needle tip of theinserter device with the aqueous drainage device loaded therein.

FIGS. 4A through 4G are schematic illustrations of the deployment of theaqueous drainage device of FIGS. 2A and 2B utilizing the inserter deviceof FIGS. 3A through 3D.

FIGS. 5A through 5D are illustrations showing the aqueous drainagedevice of FIGS. 2A and 2B implanted into the eye to shunt aqueous humorfrom the anterior chamber to a space between Tenon's membrane and thesclera of the eye.

FIGS. 6A through 6C are schematic illustrations of a methodology forimplanting the aqueous drainage device of FIGS. 2A and 2B into the eyesuch that the device shunts aqueous humor from the anterior chamber ofthe eye to a space defined between Tenon's membrane and the sclera ofthe eye.

FIGS. 7A and 7B are schematic views of the aqueous drainage device ofFIGS. 2A and 2B, which illustrate the dimensions of an exemplaryembodiment of the device.

FIGS. 8A through 8G are schematic illustrations of an alternate aqueousdrainage device in addition to operations that utilize an inserterdevice for deploying such aqueous drainage device into the eye inaccordance with the present invention.

FIG. 9 is a schematic view of an alternate embodiment of the needle tipof the inserter device of FIGS. 3A-3D.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As used herein, the term “distal” is generally defined as in thedirection of the eye of the patient, or away from a user of theapparatus/device. Conversely, “proximal” generally means in thedirection away from the eye of the patient, or toward the user of thesystem/apparatus/device.

Turning now to FIGS. 2A and 2B, there is shown an aqueous drainage tube100 for treating glaucoma in accordance with the present invention. Theaqueous drainage tube 100 includes an elongate tubular body 102 with afixation tab 104 that extends radially from the central axis of the body102. Preferably, the fixation tab 104 is positioned at or near themidpoint of the body 102 and includes a narrow portion 106A that extendsto a wide portion 106B. The distal end of the body 102 preferably formsa sharp tip 108 as shown in FIG. 2A.

The aqueous drainage tube 100 is preferably formed from a polyolefiniccopolymer material having a triblock polymer backbone comprisingpolystyrene-polyisobutylene-polystyrene, which is herein referred to as“SIBS”. SIBS can also be referred to aspoly(styrene-b-isobutylene-b-styrene) where b stands for “block”. Highmolecular weight polyisobutylene (PIB) is a soft elastomeric materialwith a Shore hardness of approximately 10A to 30A. When copolymerizedwith polystyrene, it can be made at hardnesses ranging up to thehardness of polystyrene, which has a Shore hardness of 100D. Thus,depending on the relative amounts of styrene and isobutylene, the SIBSmaterial can have a range of hardnesses from as soft as Shore 10A to ashard as Shore 100D. In this manner, the SIBS material can be adapted tohave the desired elastomeric and hardness qualities. In the preferredembodiment, the SIBS material of the aqueous drainage tube 100 has ahardness less than Shore 80A. Details of the SIBS material is set forthin U.S. Pat. Nos. 5,741,331; 6,102,939; 6,197,240; 6,545,097, which arehereby incorporated by reference in their entirety. The SIBS material ofthe aqueous drainage tube 100 may be polymerized under control meansusing carbocationic polymerization techniques such as those described inU.S. Pat. Nos. 4,276,394; 4,316,973; 4,342,849; 4,910,321; 4,929,683;4,946,899; 5,066,730; 5,122,572; and Re 34,640, each herein incorporatedby reference in its entirety. The amount of styrene in the copolymermaterial is preferably between about 16 mole % to 30 mole % and mostpreferably between 20 mole % and 27 mole %. The styrene and isobutylenecopolymer materials are preferably copolymerized in solvents.

The diameter of the lumen 110 of the aqueous drainage tube 100 ispreferably in the range between 0.0025 inches to 0.006 inches. The outerdiameter of the aqueous drainage tube 100 is preferably less than 0.02inches and most preferably on the order of 0.01 inches. The appropriatelumen diameter will vary among patients depending on the IOP of thepatient and thus is selected by the physician as desired.Advantageously, this range of small lumen diameters limits aqueous flowthrough the tube and provides for control over IOP without the need forunidirectional valves. The preferred SIBS material of the aqueousdrainage tube 100 provides superb biocompatibility and biostabilitycharacteristics. Moreover, animal tests have shown that surprisingly itwill not encapsulate in the eye, and thus can be used to provideunobstructed drainage from the anterior chamber of the eye.

It is expected that alternative polymeric materials are suitable for thepractice of the present invention. Such alternative polymeric materialspreferably include polyisobutylene-based material capped with a glassysegment. The glassy segment provides a hardener component for theelastomeric polyisobutylene. The glassy segment preferably does notcontain any cleavable group which will release in the presence of bodyfluid inside the human eye and cause toxic side effects and cellencapsulation. The glassy segment can be a vinyl aromatic polymer (suchas styrene, α-methylstyrene, or a mixture thereof), or a methacrylatepolymer (such as methylmethacrylate, ethylmethacrylate,hydroxymethalcrylate, or a mixture thereof). Such materials preferablyhave a general block structure with a central elastomeric polyolefinicblock and thermoplastic end blocks. Even more preferably, such materialshave a general structure:

-   -   BAB or ABA (linear triblock),    -   B(AB)_(n) or a(BA)_(n) (linear alternating block), or    -   X-(AB)_(n) or X-(BA)_(n) (includes diblock, triblock and other        radial block copolymers), where A is an elastomeric polyolefinic        block, B is a thermoplastic block, n is a positive whole number        and X is a starting seed molecule.        Such materials may be star-shaped block copolymers (where n=3 or        more) or multi-dendrite-shaped block copolymers. These materials        collectively belong to the polymeric material referred to herein        as SIBS material.

Alternatively, the aqueous drainage tube 100 can be realized fromanother soft elastomeric polymeric material. Preferably, the softelastomeric polymeric material is biocompatible and biostable within theocular environment. Moreover, it is preferable that the soft elastomericpolymeric material of the drainage tube 100 not naturally attractleukocytes and/or myofibroblasts, which protects against encapsulationof the tube in the eye, and thus provides unobstructed drainage from theanterior chamber of the eye.

The distal tip 108 of the aqueous drainage tube 100 is preferablyinserted into the anterior chamber of the eye with an inserter device200 as shown in FIGS. 3A to 4G. The inserter device 200 includes a body201 that supports a slide member 202 having a thumb grip 203 as shown inFIGS. 3A and 3B. The proximal end of a hollow needle 205 is rigidlyconnected to the slide member 202 preferably by a set screw 206. Theslide member 202 is disposed within an interior space 209 of the body201 and is capable of translation relative to the body 201 in order totranslate the needle 205 out (distal movement) and in (proximalmovement) along its central axis. An over-tube 208 extends from the noseof the body 201 as shown in FIGS. 3B through 3D. The distal portion ofthe needle 205 extends from the over-tube 208 and terminates at a sharptip 207 (FIG. 3D).

The distal portion of the needle 205 includes a guide slot 209 thatextends through the annular wall of the needle 205 in a lengthwisemanner as best shown in FIG. 3B. The width of the guide slot 209 alongmost of its length is greater than the width of the narrow portion 106Aof the fixation tab 104 and is less than the width of the wide portion106B of the fixation tab 104. In this manner, the narrow portion 106B ofthe fixation tab rides within the guide slot 209 during deployment asdescribed below. In FIGS. 3A through 3D, the elongate body 102 of theaqueous drainage tube 100 is loaded within the distal portion of thehollow needle 205.

As shown in FIG. 3A, the body 201 includes a stop 210 that cooperateswith a locking tab 211 of the slide member 202 to prohibit proximaltranslation of the slide member 202 and needle 205 in its defaultconfiguration. As shown in FIG. 4A, the user can apply an inwardpressing force (depicted by the arrow 212) to the thumb grip 203, whichcauses the locking tab 211 to deflect inward. Such deflection allows thelocking tab 211 to clear the stop 210 such that the slide member 202 andneedle 205 can translate proximally relative to the body 201.

Deployment of the aqueous drainage tube from the inserter 200 is carriedout as shown in the sequence of FIGS. 4A through 4G. Initially, theelongate body 102 of the aqueous drainage tube 100 is loaded within thedistal portion of the hollow needle 205, and the slide member 202 andneedle 205 are locked in place by the locking tab 211 and the stop 210(FIG. 3A). The user then applies an inward pressing force to the thumbgrip 203, which causes the locking tab 211 to deflect inward as shown inFIG. 4A. Such deflection allows the locking tab 211 to clear the stop210 such that the slide member 202 and needle 205 can translateproximally relative to the body 201. The relative position of theaqueous drainage tube 100 and the hollow needle 205 is shown in FIG. 4B.

The user then applies a rearward pressing force (depicted by the arrow213) on the thumb grip 203, which causes the slide member 202 and needle205 to translate proximal relative to the body 201 as shown in FIG. 4C.During such proximal translation, the proximal edge 111 of the fixationtab 104 butts up against the distal end 214 of over-tube 208 such thatthe body 102 of the aqueous drainage tube 100 partially slides out ofthe lumen of the hollow needle 205 through an opening in the tip 207 asshown in FIG. 4D.

The user continues to apply the rearward pressing force on the thumbgrip 203, which causes the slide member 202 and needle 205 to furthertranslate proximal relative to the body 201 as shown in FIG. 4E. In thisstep, the distal tip 207 of the needle 205 is retracted into theinterior of the over-tube 208. During such proximal translation, theproximal edge 111 of the fixation tab 104 remains butted up against thedistal end 214 of over-tube 208 such that the body 201 of the aqueousdrainage tube 100 is further ejected from the lumen of the hollow needle205 as best shown in FIG. 4F.

Finally, the user retracts the inserter assembly 200 such that theentire aqueous drainage tube 100 is ejected from the over-tube 208 asshown in FIG. 4G.

The body 201 and slide member 203 of the inserter device 200 can berealized from an engineering plastic such as ABS, Xenoy, Ultem,polycarbonate, rigid polyurethane, polyethylene, polypropylene, nylonand the like. For disposable applications, it is preferred that thesecomponents be injected molded. If the inserter device is not to bedisposable (i.e., it is sterilizable and reusable), all components canbe made from medical grade metals such as stainless steel, galvanizedaluminum, gold, platinum, and the like. Lubricant may be applied to theslide member 202 to help it translate from side to side.

Turning now to FIGS. 5A through 5D, there is shown the aqueous drainagetube 100 of the present invention implanted such that its distal tip 108is positioned within the anterior chamber 20 of the eye and its proximalend 112 is positioned in a pouch 300 formed between Tenon's membrane 36and the sclera 26. The pouch 300 is closed and a space 302 betweenTenon's membrane 36 and the sclera 26 remains in the plane of the pouch300. The aqueous drainage tube 100 shunts aqueous humor from theanterior chamber 20 to the space 302, which forms a shallow bleb.Aqueous fluid is absorbed into the adjacent tissue and ends up in thevenous system in the eye or in the tear film.

The pouch 300 extends rearward from a location at or near the limbus tothe posterior portion of the globe of the eye near the equator of theeye as best shown in FIG. 5B. The pouch 300 is preferably defined bymaking an incision through Tenon's membrane 36 into theconjuctiva-sclera and then dissecting and separating Tenon's membrane 36from the sclera 26 over the area of the pouch 300. The distal end 108 ofthe aqueous drainage tube 100 is inserted through a needle tract thepasses through the angle 28 to the anterior chamber 20 of the eye (FIGS.5B and 5C). The proximal end 112 of the aqueous drainage tube 100 islocated within the rear of the pouch 300 (FIG. 5C). After properpositioning of the tube 100, the pouch 300 is closed. A sponge, blottingpaper or other suitable carrier loaded with an anti-proliferative agentcan be placed within the pouch 300 before it is closed. Theanti-proliferative agent may be, for example, mitomycin C or5-Fuorouracil or other antimetabolites or other suitable drug(s) orcompound(s) that releases over time and functions to minimize fibrosisof the conjuctiva-sclera to Tenon's membrane, thereby maintaining thestructure of the pouch 300 over an extended period of time. A closedspace 302 between Tenon's membrane 36 and the sclera 26 remains in theplane of the pouch 300 (FIG. 5D). Aqueous humor flows from the anteriorchamber 20 through the lumen of the tube 100 and into the closed space302. The closed space 302 prevents bacteria from entering the tube 100and infecting the eye. Aqueous humor exiting the tube 100 and enteringthe closed space 302 creates a very shallow bleb. The bleb fluid mayfilter through the conjunctiva 30 into the tears, and the fluid may beabsorbed through the capillaries that interpenetrate the conjunctiva 30.A fraction of the aqueous humor contained in the bleb may potentiallyseep through the permeable sclera 26 and be absorbed by the choroidalcapillaries. The fixation tab 104 of the aqueous drainage tube 100 ispreferably positioned near the limbus 32 where the conjunctiva 30adheres very strongly to the sclera 26, thus sealing the fixation tab104 along its periphery with time and thus preventing the tube 100 frommigrating into, or away from, the anterior chamber 20 of the eye.

In accordance with the present invention, the aqueous drainage tube 100is implanted into the position shown in FIGS. 5A through 5D utilizing amethod shown in FIGS. 6A through 6C. FIG. 6A shows a very small sectionof the eye, including the anterior chamber 20, the conjunctiva 30 andunderlying sclera 26, and the limbus 32. The pouch 300 is made bydisinserting the conjunctiva 30 at the limbus 32 in an incision area 302less than one quadrant using miniature scissors (Vannas scissors orsimilar) and dissecting and separating Tenon's membrane 36 from thesclera 26 over a few millimeters. Then, holding the edge of the pouch300 at its center with toothed forceps, the closed tips of a pair ofblunt scissors (e.g. Westcott or similar) are slowly pushed downwardtoward the eye equator and open up to separate (delaminate) Tenon'smembrane 36 from the sclera 26. The scissors are again closed; its tipspushed further forward and reopened to separate a larger area of Tenon'smembrane 36. The process is repeated until the tips of the scissors are17 to 20 mm away from the limbus 32. The pouch 300 thusly created inlarger at the equatorial base than at the limbal entry.

The pouch 300 is formed adjacent to the limbus 32. A mark, centered inthe middle of the conjunctival opening is made 2 mm behind the limbus'edge using a blunt caliper. A tissue ink can be used on the tip of thecaliper to increase contrast of the tissue mark. A solution filledsyringe equipped with a needle (preferably of 27 gauge) is prepared andair bubbles are removed from the syringe and from the tip. The tip ofthe needle is then positioned at the mark made on the sclera and asurgical track is fashioned to connect the scleral outer wall to theanterior chamber by pushing the needle is a plane such that the tip ofthe needle enters the eye through the angle 28 into the anterior chamber20. In this manner, the needle tract passes through theconjuctiva-sclera in the vicinity of the angle 28 and into the anteriorchamber 20. The surgeon may elect to fill the anterior chamber 20 with apharmacological solution, such as epinephrine. After a few seconds, theneedle is slowly retracted. The aqueous drainage tube 100 is loaded andlocked in the distal portion of the needle 205 of the inserter device200, and the sharp tip 207 of the inserter device 200 is inserted intothe needle track until its tip 207 exits into the anterior chamber 20 ofthe eye. The aqueous drainage tube 100 is then deployed from theinserter device 200 as described above with respect to FIGS. 3A through4G. FIG. 6B shows the position of the tube 100 within the pouch 300after deployment from the inserter device 200. The pouch 300 is thenclosed with sutures 304 as shown in FIG. 6C. Instead of sutures, bipolardiathermy coagulation, laser welding or cyanoacrylate can be used toclose the pouch 300.

Tissue fixation is always a source of inflammation and the fixationpoint must be as far away as possible from the implant. To minimizeinflammation as well as reduce surgical time, the pouch 300 can also becreated by disinsertion of the conjunctiva at the limbus and, startingat one edge of the disinsertion, cutting the conjuctival tissueposteriorly for about 3 mm, thus creating a flap door. After placementof the distal end 112 of the tube 100 in the pouch 300, the freed edgeof the conjunctiva 30 is juxtaposed about 2 mm past its originalposition and held taut with a single suture, or a single laser weld, ora single-point bipolar diathermy coagulation, or with a single dot ofcyanoacrylate. The edge of the conjunctiva 30 along the limbus 32 isnever treated, but left intact to prevent tissue necrosis that engendersfibrosis. The cornea-limbal epithelium cells will rapidly recover thewound edge (1 hour or less), sealing the conjunctival limbus.

A sponge, blotting paper or other suitable carrier loaded with one ormore therapeutic agents can be placed within the pouch 300 before it isclosed. Such therapeutic agent(s) release over time and minimizesfibrosis of Tenon's membrane to the sclera, thereby preventingre-lamination and closure of the bleb space 302. The therapeuticagents(s) can include cytostatic agents (i.e., anti-proliferation agentsthat prevent or delay cell division, for example, by inhibitingreplication of DNA, and/or by inhibiting spindle fiber formation, and/orby inhibiting cell migration) or other agents that minimize fibrosis orblood clots. Examples of such therapeutic agents are described below.

Alternatively, the polymeric aqueous humor drainage device 100 (or partsthereof) can be loaded with one or more therapeutic agents that releaseover time and minimize fibrosis of the Tenon's membrane to the sclera,thereby preventing re-lamination and closing of the bleb space 302. Thetherapeutic agents(s) loaded into the device 100 can include cytostaticagents (i.e., anti-proliferation agents that prevent or delay celldivision, for example, by inhibiting replication of DNA, and/or byinhibiting spindle fiber formation, and/or by inhibiting cell migration)or other agents that minimize fibrosis or blood clots. Examples of suchtherapeutic agents follow.

Representative examples of therapeutic agents include the following:Visudyne, Lucentis (rhuFab V2 AMD), Combretastatin A4 Prodrug, SnET2,H8, VEGF Trap, Cand5, LS 11 (Taporfin Sodium), AdPEDF, RetinoStat,Integrin, Panzem, Retaane, Anecortave Acetate, VEGFR-1 mRNA, ARGENTcell-signalling technology, Angiotensin II Inhibitor, Accutane forBlindness, Macugen (PEGylated aptamer), PTAMD, Optrin, AK-1003, NX 1838,Antagonists of avb3 and 5, Neovastat, Eos 200-F and any other VEGFinhibitor.

Other therapeutic agents can be used such as: mitomycin C,5-fluorouracil, corticosteroids (corticosteroid triamcinolone acetonideis most common), modified toxins, methotrexate, adriamycin,radionuclides (e.g., such as disclosed in U.S. Pat. No. 4,897,255,herein incorporated by reference in it entirety), protein kinaseinhibitors (including staurosporin, which is a protein kinase Cinhibitor, as well as a diindoloalkaloids and stimulators of theproduction or activation of TGF-beta, including tamoxifen andderivatives of functional equivalents, e.g., plasmin, heparin, compoundscapable of reducing the level or inactivating the lipoprotein Lp(a) orthe glycoprotein apolipoprotein(a) thereof), nitric oxide releasingcompounds (e.g., nitroglycerin) or analogs or functional equivalentsthereof, paclitaxel or analogs or functional equivalents thereof (e.g.,taxotere or an agent based on Taxol®, whose active ingredient ispaclitaxel), inhibitors of specific enzymes (such as the nuclear enzymeDNA topoisomerase II and DAN polymerase, RNA polyermase, adenl guanylcyclase), superoxide dismutase inhibitors, terminaldeoxynucleotidyl-transferas, reverse transcriptase, antisenseoligonucleotides that suppress cell proliferation, angiogenesisinhibitors (e.g., endostatin, angiostatin and squalamine), rapamycin,cerivastatin, and flavopiridol and suramin and the like.

Other examples of therapeutic agents include the following: peptidic ormimetic inhibitors, such as antagonists, agonists, or competitive ornon-competitive inhibitors of cellular factors that may triggerproliferation of cells or pericytes (e.g., cytokines (for example,interleukins such as IL-1), growth factors (for example, PDGF, TGF-alphaor -beta, tumor necrosis factor, smooth muscle—and endothelioal—derivedgrowth factors such as endothelin or FGF), homing receptors (forexample, for platelets or leukocytes), and extracellular matrixreceptors (for example, integrins).

Representative examples of useful therapeutic agents in the category ofagents that address cell proliferation include: subfragments of heparin,triazolopyrimidine (for example, trapidil, which is a PDGF antagonist),lovastatin; and prostaglandins E1 or I2.

Several of the above and numerous additional therapeutic agentsappropriate for the practice of the present invention are disclosed inU.S. Pat. Nos. 5,733,925 and 6,545,097, both of which are hereinincorporated by reference in their entirety.

If desired, a therapeutic agent of interest can be provided at the sametime as the polymer from which the device 100 is realized, for example,by adding it to a polymer melt during thermoplastic processing or byadding it to a polymer solution during solvent-based processing.Alternatively, a therapeutic agent can be provided after formation ofthe device or device portion. As an example of these embodiments, thetherapeutic agent can be dissolved in a solvent that is compatible withboth the device polymer and the therapeutic agent. Preferably, thedevice polymer is at most only slightly soluble in this solvent.Subsequently, the solution is contacted with the device or deviceportion such that the therapeutic agent is loaded (e.g., byleaching/diffusion) into the copolymer. For this purpose, the device ordevice portion can be immersed or dipped into the solution, the solutioncan be applied to the device or component, for example, by spraying,printing dip coating, immersing in a fluidized bed and so forth. Thedevice or component can subsequently be dried, with the therapeuticagent remaining therein.

In another alternative, the therapeutic agent may be provided within amatrix comprising the polymer of the device. The therapeutic agent canalso be covalently bonded, hydrogen bonded, or electrostatically boundto the polymer of the device. As specific examples, nitric oxidereleasing functional groups such as S-nitroso-thiols can be provided inconnection with the polymer, or the polymer can be provided with chargedfunctional groups to attach therapeutic groups with oppositely chargedfunctionalities.

In yet another alternative embodiment, the therapeutic agent can beprecipitated onto one or more surfaces of the device or device portion.These one or more surface(s) can be subsequently covered with a coatingof polymer (with or without additional therapeutic agent) as describedabove.

Hence, when it is stated herein that the polymer is “loaded” withtherapeutic agent, it is meant that the therapeutic agent is associatedwith the polymer in a fashion like those discussed above or in a relatedfashion.

In some instances a binder may be useful for adhesion to a substrate.Examples of materials appropriate for binders in connection with thepresent invention include silanes, titanates, isocyanates, carboxyls,amides, amines, acrylates hydroxyls, and epoxides, including specificpolymers such as EVA, polyisobutylene, natural rubbers, polyurethanes,siloxane coupling agents, ethylene and propylene oxides.

It also may be useful to coat the polymer of the device (which may ormay not contain a therapeutic agent) with an additional polymer layer(which may or may not contain a therapeutic agent). This layer mayserve, for example, as a boundary layer to retard diffusion of thetherapeutic agent and prevent a burst phenomenon whereby much of theagent is released immediately upon exposure of the device or deviceportion to the implant site. The material constituting the coating, orboundary layer, may or may not be the same polymer as the loadedpolymer. For example, the barrier layer may also be a polymer or smallmolecule from the following classes: polycarboxylic acids, includingpolyacrylic acid; cellulosic polymers, including cellulose acetate andcellulose nitrate; gelatin; polyvinylpyrrolidone; cross-linkedpolyvinylpyrrolidone; polyanhydrides including maleic anhydridepolymers; polyamides; polyvinyl alcohols; copolymers of vinyl monomerssuch as EVA (ethylene-vinyl acetate copolymer); polyvinyl ethers;polyvinyl aromatics; polyethylene oxides; glycosaminoglycans;polysaccharides; polyesters including polyethylene terephthalate;polyacrylamides; polyethers; polyether sulfone; polycarbonate;polyalkylenes including polypropylene, polyethylene and high molecularweight polyethylene; halogenated polyalkylenes includingpolytetrafluoroethylene; polyurethanes; polyorthoesters; polypeptides,including proteins; silicones; siloxane polymers; polylactic acid;polyglycolic acid; polycaprolactone; polyhydroxybutyrate valerate andblends and copolymers thereof; coatings from polymer dispersions such aspolyurethane dispersions (BAYHDROL.RTM., etc.); fibrin; collagen andderivatives thereof; polysaccharides such as celluloses, starches,dextrans, alginates and derivatives; and hyaluronic acid.

Copolymers and mixtures of the above are also contemplated.

It is also possible to form the aqueous humor drainage device (or deviceportion) with blends by adding one or more of the above or otherpolymers to a block copolymer. Examples include the following:

-   -   blends can be formed with homopolymers that are miscible with        one of the block copolymer phases. For example, polyphenylene        oxide is miscible with the styrene blocks of        polystyrene-polyisobutylene-polystyrene copolymer. This should        increase the strength of a molded part or coating made from        polystyrene-polyisobutylene-polystyrene copolymer and        polyphenylene oxide.    -   blends can be made with added polymers or other copolymers that        are not completely miscible with the blocks of the block        copolymer. The added polymer or copolymer may be advantageous,        for example, in that it is compatible with another therapeutic        agent, or it may alter the release rate of the therapeutic agent        from the block copolymer (e.g.,        polystyrene-polyisobutylene-polystyrene copolymer).    -   blends can be made with a component such as sugar (see list        above) that can be leached from the device or device portion,        rendering the device or device component more porous and        controlling the release rate through the porous structure.

The release rate of therapeutic agent from the therapeutic-agent-loadedpolymers of the present invention can be varied in a number of ways.Examples include:

-   -   varying the molecular weight of the block copolymers;    -   varying the specific constituents selected for the elastomeric        and thermoplastic portions of the block copolymers and the        relative amounts of these constituents;    -   varying the type and relative amounts of solvents used in        processing the block copolymers;    -   varying the porosity of the block copolymers;    -   providing a boundary layer over the block copolymer; and    -   blending the block copolymer with other polymers or copolymers.

Moreover, although it is seemingly desirable to provide control over therelease of the therapeutic agent (e.g., as a fast release (hours) or asa slow release (weeks)), it may not be necessary to control the releaseof the therapeutic agent. In such embodiments, one or more of thetherapeutic drug agents described herein (e.g., an antiproliferativeagent derived from mitomycin C or 5-fluorouracil) may be injected intothe pouch at the time of surgery.

FIGS. 7A and 7B illustrate the dimensions of an exemplary embodiment ofthe aqueous drainage tube 100 of the present invention.

FIG. 8A through 8G illustrate an alternate design of an aqueous drainagedevice in accordance with the present invention. The device 100′ ismeant to prevent migration of the device 100′ into and outside of theeye immediately upon implantation. As show in FIGS. 8A and 8B, thedevice 100′ includes an elongate hollow tubular member 301 with the sameconstruction and dimensions as the tubular member 102 described above.Two fixation tines 302, 303 are attached to the tubular member 301 suchthat they extend transverse thereto. Aqueous humor is meant to flowthrough the hollow tubular member 301 in the direction of the arrow 304.The fixation tine 302 is disposed near the entrance to the hollowtubular member 301. The fixation tine 303 is preferably disposed nearthe midpoint of the hollow tubular member 301.

The entire device 100′ is preferably realized from soft elastomeric SIBSmaterial with a hardness less than Shore 80A. The preferred SIBSmaterial of the device 100′ provides superb biocompatibility andbiostability characteristics. Moreover, animal tests have shown thatsurprisingly it will not encapsulate in the eye, and thus can be used toprovide unobstructed drainage from the anterior chamber of the eye.Alternatively, the device 100′ can be realized from another softelastomeric polymeric material. Preferably, the soft elastomericpolymeric material is biocompatible and biostable within the ocularenvironment. Moreover, it is preferable that the soft elastomericpolymeric material of the device 100′ not naturally attract leukocytesand/or myofibroblasts, which protects against encapsulation of the tubein the eye, and thus provides unobstructed drainage from the anteriorchamber of the eye.

As shown in FIG. 8C, the tine 302 is inserted into a slot 209′ thatextends along the distal portion of the tip 205′ of an inserter 200′.The inserter 200′ is similar to the inserter 200 described above.However, in lieu of the over-tube 8 a plunger 215 is connected to theslide member (not shown). The needle 205′ is held stationary by fixingit permanently to the body (not shown) of the inserter 200′. The plunger215 is capable of distal translation relative to the inserter body byapplying an axial pushing force to the thumb grip (not shown) of theslide member. A locking mechanism, similar to the lock and stopdescribed above, may be provided to inhibit such distal translationuntil the user presses on the thumb grip. The aqueous drainage device100′ is deployed by applying an axial pushing force in the distaldirection to the thumb grip of the slide member, which causes theplunger 215 to move distally and push against the tine 302 of the device100′, thereby ejecting the device 100′ from the tip 207′ of the inserter200′. The tip 207′ is preferably realized by two sharp cutting edgesthat extend to blunt rounded edges, which terminate proximally at theguide slot 209′ in the manner shown in FIG. 3E and discussed above indetail.

FIG. 8D shows the tip 207′ of the inserter 200′ inserted into theanterior chamber 20 through the angle 28 via a pouch defined betweenTenon's membrane 36 and the sclera 26 (FIG. 5A). The device 100′ isdeployed by applying an axial pushing force in the distal direction tothe thumb grip of the slide member, which causes the plunger 215 to movedistally and push against the tine 302 of the device 100′, therebyejecting the device 100′ from the tip 207′ in the manner shown in FIGS.8E through 8G. The pushing action of the plunger 215 first causes thetine 302 to pass through the limbus passageway defined by the needle tip207′ of the inserter 200′ as shown in FIG. 8E. The continued pushingaction of the plunger 215 then causes the bottom portion of the hollowtubular member 301 to pass through the limbus passageway as shown inFIG. 8F. The device 100′ is then retracted proximally, which causes thetine 303 and the top portion of the hollow tubular member 301 to beejected from the needle tip 207′ of the inserter 200′ as shown in FIG.8G. In the deployed configuration, the two tines 302, 303 are disposedon opposite sides of the sclera in the vicinity of the angle 28 as shownand thus prevent migration of the device 100′ into and outside of theeye immediately upon implantation. After proper positioning of the tube100′, the pouch is closed. A closed space between Tenon's membrane 36and the sclera 26 remains in the plane of the pouch (FIG. 5D). Aqueoushumor flows from the anterior chamber 20 through the lumen of the tube100′ and into this closed space. The closed space prevents bacteria fromentering the tube 100′ and infecting the eye. Aqueous humor exiting thetube 100′ and entering the closed space creates a very shallow bleb. Thebleb fluid may filter through the conjunctiva into the tears, and thefluid may be absorbed through the capillaries that interpenetrate theconjunctiva. A fraction of the aqueous humor contained in the bleb maypotentially seep through the permeable sclera 26 and be absorbed by thechoroidal capillaries. A sponge, blotting paper or other suitablecarrier loaded with one or more therapeutic agents can be placed withinthe pouch before it is closed. Such therapeutic agent(s) release overtime and minimize fibrosis of the sclera to Tenon's membrane, therebypreventing re-lamination and closing of the bleb space. Alternatively,the polymeric aqueous humor drainage device 100′ (or parts thereof) canbe loaded with such therapeutic agents. The therapeutic agents(s) loadedinto the device 100′ can include any one of the therapeutic agents asdescribed above.

In an alternate embodiment shown in FIG. 9, the sharp tip 207 of theneedle 210 may be realized by two sharp cutting edges 215A, 215B thatextend proximally and radially outward from a distal-most sharp point216, which is aligned along the central axis of the body 102. Theproximal end of the edges 215A, 215B extend to arcuate blunt roundededges 217A, 217B that terminate proximally at the guide slot 209. Thesharp edges 215A, 215B and the rounded edges 217A, 217B outline anopening 218 through the annular wall of the hollow body 201 into thelumen of the hollow body as shown. The sharp point 216 and the sharpcutting edges 215A, 215B facilitate piercing the eye tissue at thedesired insertion point in order to form the needle tract that leadsthrough the eye tissue into the anterior chamber. The blunt roundededges 217A, 217B facilitate the slidable movement of the needle tip 207through the needle tract and into the anterior chamber of the eye asdiscussed above. It is contemplated that this design does not require aseparate needle to form the needle tract as described above. In otherwords, the same needle can be used to form the needle tract and deploythe aqueous humor drainage device therethrough.

There have been described and illustrated herein several embodiments ofglaucoma implant devices that divert aqueous humor from the anteriorchamber of the eye and surgical methods associated therewith. Whileparticular embodiments of the invention have been described, it is notintended that the invention be limited thereto, as it is intended thatthe invention be as broad in scope as the art will allow and that thespecification be read likewise.

Thus, while particular methods of manufacture have been disclosed, itwill be understood that other manufacture methods can be used. Forexample, because the copolymer materials described herein have athermoplastic character, a variety of standard thermoplastic processingtechniques can be used to for the devices described herein. Suchtechniques include compression molding, injection molding, blow molding,spinning, vacuum forming and calendaring, and extrusion into tubes andthe like. Such devices can also be made using solvent-based techniquesinvolving solvent casting, spin coating, solvent spraying, dipping,fiber forming, ink jet techniques and the like.

Also, while it is preferred that the implant device be realized by asimple tubular structure, it will be recognized that adaptations may bemade of such structures. For example, other duct forming structures andshapes can be used. In another example, the device may include holesthrough the side wall of the tubular structure. In another example, thetubular structure may include multiple lumens therein.

It is also preferred that the elongate tubular structure be constructedof a soft and flexible material that allows for compression of thetubular structure at sufficiently high ocular pressures to provide for afluid path between the needle tract through the sclera and thecompressed tubular structure and out into the surrounding ocular tissue(e.g., the Tenon's membrane pouch as described herein). This releasespressure from the anterior chamber of the eye, for example, in the eventthat the lumen of the elongate tubular structure is clogged. When theocular pressure drops to normal levels, the tubular structure returns toits normal uncompressed state and the fluid path through the needletract is sealed.

Alternatively, the elongate tubular structure might possibly beconstructed without a lumen and made sufficiently compressible such thataqueous humor will compress the tubular structure and travel between thecompressed tubular structure and the needle tract in order to releasepressure from the anterior chamber of the eye. In either configuration,the compressible tubular structure cooperates with the needle tract toprovide a pressure relief valve for aqueous humor within the anteriorchamber of the eye.

It will therefore be appreciated by those skilled in the art that yetother modifications could be made to the provided invention withoutdeviating from its spirit and scope as claimed.

1. A surgical method for diverting aqueous humor from the anterior chamber of the eye, the surgical method comprising: providing an implantable aqueous humor drainage device having an elongate duct structure having two ends opposite one another and a fixation member that extends radially outward from said elongate duct structure, said fixation member spaced apart from said ends of said elongate duct structure; creating a pouch by separating Tenon's membrane from the sclera in a region extending rearward of the limbus of the eye, wherein the pouch defines interior space bounded above by a portion of Tenon's membrane disposed rearward of the limbus and bounded below by a portion of the sclera disposed rearward of the limbus; forming an opening through the sclera into the anterior chamber of the eye; inserting a distal portion of the elongate duct structure through the opening through the sclera into the anterior chamber of the eye; positioning the fixation member and a proximal portion of the elongate duct structure in the pouch, the fixation member for fixing the elongate duct structure in the pouch; and closing the pouch.
 2. A surgical method according to claim 1, wherein: the pouch is closed with sutures.
 3. A surgical method according to claim 1, further comprising: inserting a drug carrier into the pouch, wherein the drug carrier is loaded with at least one therapeutic agent that minimizes fibrosis of ocular tissue.
 4. A surgical method according to claim 3, wherein: said at least one therapeutic agent is selected from the group including an agent containing verteporfin, an agent containing ranibizumab, an agent containining combretastatin, an agent containing tin ethyl etiopurpurin, an agent containing hydrochiorothiazide and telmisartan, an agent that binds or inhibits Vascular Endothelial Growth Factor, an agent containing Taporfin Sodium, an agent carrying the Pigment Epithelium—Derived Factor (PEDF) gene, an agent carrying endostatin and angiostatin, Integrin, an agent containing 2-methoxyestradiol, Anecortave Acetate, an agent that inhibits Angiotensin II, an agent containing isotretinoin, an agent containing PEGylated aptamer, an agent containing Motexafin lutetium mitomycin C, 5-fluorouracil, corticosteroids, modified toxins, methotrexate, adriamycin, radionuclides, protein kinase inhibitors, nitric oxide releasing compounds or analogs or functional equivalents thereof, paclitaxel or analogs or functional equivalents, inhibitors of specific enzymes, superoxide dismutase inhibitors, terminal deoxynucleotidyl-transferas, reverse transcriptase, antisense oligonucleotides that suppress cell proliferation, angiogenesis inhibitors, rapamycin, cerivastatin, and flavopiridol and suramin and the like, peptidic or mimetic inhibitors, pericytes, growth factors, homing receptors, extracellular matrix receptors, subfragments of heparin, triazolopyrimidine, lovastatin, and prostaglandins E1 or I2.
 5. A surgical method according to claim 1, wherein: a portion of the aqueous humor drainage device is realized from a polymeric material that is loaded with at least one therapeutic agent that minimizes fibrosis of ocular tissue.
 6. A surgical method according to claim 5, wherein: said at least one therapeutic agent is selected from the group including an agent containing verteporfin, an agent containing ranibizumab, an agent containing combretastatin, an agent containing tin ethyl etiopurpurin, an agent containing hydrochiorothiazide and telmisartan, an agent that binds or inhibits Vascular Endothelial Growth Factor, an agent containing Taporfin Sodium, an agent carrying the Pigment Epithelium—Derived Factor (PEDF) gene, an agent carrying endostatin and angiostatin, Integrin, an agent containing 2-methoxyestradiol, Anecortave Acetate, an agent that inhibits Angiotensin II, an agent containing isotretinoin, an agent containing PEGylated aptamer, an agent containing Motexafin lutetium mitomycin C, 5-fluorouracil, corticosteroids, modified toxins, methotrexate, adriamycin, radionuclides, protein kinase inhibitors, nitric oxide releasing compounds or analogs or functional equivalents thereof, paclitaxel or analogs or functional equivalents, inhibitors of specific enzymes, superoxide dismutase inhibitors, terminal deoxynucleotidyl-transferas, reverse transcriptase, antisense oligonucleotides that suppress cell proliferation, angiogenesis inhibitors, rapamycin, cerivastatin, and flavopiridol and suramin and the like, peptidic or mimetic inhibitors, pericytes, growth factors, homing receptors, extracellular matrix receptors, subfragments of heparin, triazolopyrimidine, lovastatin, and prostaglandins E1 or I2.
 7. A surgical method according to claim 1, wherein: the opening through the sclera into the anterior chamber of the eye is created with a needle.
 8. A surgical method according to claim 1, wherein: the fixation member comprises a tab that extends radially outward along a length of said elongate duct structure.
 9. A surgical method according to claim 8, wherein: said tab comprises a first part that extends to a second part, wherein said first part is narrower in thickness than said second part.
 10. A surgical method according to claim 1, wherein: the fixation member comprises a tine that extends in a direction transverse to a central axis of said elongate duct structure.
 11. A surgical method according to claim 1, wherein: the pouch extends rearward to a posterior portion of the globe of the eye adjacent the equator of the eye.
 12. A surgical method according to claim 11, wherein: the pouch extends rearward at least 15 mm away from the limbus.
 13. A surgical method according to claim 12, wherein: the pouch extends rearward 17 mm to 20 mm away from the limbus.
 14. A surgical method according to claim 11, wherein: the posterior portion of the pouch is larger than a portion of the pouch adjacent the limbus.
 15. A surgical method according to claim 1, wherein: the pouch is created by delaminating Tenon's membrane from the sclera with blunt scissors.
 16. A surgical method according to claim 1, further comprising: deploying the aqueous humor drainage device from a tool having a hollow support member that supports the aqueous humor drainage device therein.
 17. A surgical method according to claim 16, further comprising: inserting a distal end of the hollow support member of the tool into the anterior chamber of the eye through the opening through the sclera for deployment of the aqueous humor drainage device. 